Chronic traumatic encephalopathy: a potential late and under recognized consequence of rugby union?

The association between exposure to head injury and increased risk of neurodegenerative disease, specifically chronic traumatic encephalopathy (CTE), is widely recognized. Historically, this was largely considered a phenomenon restricted to boxers, with more recent case series identifying further 'high risk' individuals, such as former American footballers, or military personnel. However, in all cases thus far reported, it is clear that it is the exposure to head injury which is associated with increased dementia risk, and not the circumstances or environment of exposure. As such, there is considerable potential for under-recognition of CTE in patients presenting with neurodegenerative disease, particularly where head injury exposure might have been historical and through sport. This article reviews current understanding of CTE and, via an illustrative case in rugby union, highlights the value of a detailed history on head injury and also draws attention to imaging studies in assessing patients with neurodegenerative disease.